Mercury 9.9 2 stroke water cooling problem

[jplloyd]

Hi,

I have a 2004 Mercury 9.9HP 2-stroke motor, which overheated and seized a few minutes into my first trip out of the season yesterday. It started ok this morning, but there wasn't any water (just very hot exhaust) coming out of the water indicator hole. So I pulled the motor off the boat and removed the lower unit and checked the impeller, which was in good shape. I put it all back together, and started it up with a water supply on the flushing attachment. Still no water coming out of the indicator hole, but the pump is definitely pumping - there's lots of water coming out of the hole halfway up the driveshaft housing when the motor revs.

Any suggestions? Perhaps a thermostat? Perhaps a blockage or bad connection between the pump and the water tube? It wasn't clear to me from the service manual which way around the guide that goes between the water pump and the water tube should go, so I may have installed that upside down. Which way around should it go?

Thanks,

James

 

[ddwilson]

Re: Mercury 9.9 2 stroke water cooling problem

it could be a bad connection of the tube, the angled end of the guide goes up make sure the rubber part in the water pump is not dried out or cracked . Make an adapter from rubber hose that will connect to the copper line that goes to the power head and connect to a garden hose turn on water and see if you have any water coming through the engine will show quickly if plugged up

 

[MH Hawker]

Re: Mercury 9.9 2 stroke water cooling problem

It could be a piece of the pump impeller thats broken lose some time in the past blocking a passage.